Generally, acrolein and acrylic acid are produced by oxidizing propylene which is a fossil resource. However, there are concerns over the increase of carbon dioxide in the air in the production method depending on fossil resources. There are also fears of depletion of fossil resources in future.
Therefore, using glycerol in the acrolein production has been studied which is generated as a by-product during the production of Bio Diesel Fuel from vegetable oil or animal fat or production of soap. That is, a method for producing acrolain by dehydrating glycerol generated as a by-product has been studied.
Here, since glycerol generated from vegetable oil has advantages that there are no fears of depletion since the glycerol is derived from plants and that the glycerol does not substantially contribute to the increase of carbon dioxide in air since the carbon source of the glycerol is carbon dioxide in the air. Animal oil and fat are the resource produced by the intake of feedstuff such as vegetable oil by livestock and it can be considered that the carbon source of the animal oil and fat is the carbon dioxide in the air.
As a method for producing acrolein by glycerol dehydration reaction, a method of using an acid catalyst has been known.
For example, U.S. Pat. No. 1,916,743 (Patent Document 1) discloses a method of reacting glycerol in a vapor phase in the presence of a catalyst supporting copper phosphate (I). However, the document does not teach reacting glycerol in the presence of a compound containing a heteroatom.
JP-A-2006-290815 (Patent Document 2) discloses a method of reacting glycerol by dissolving or dispersing glycerol in a solvent. However, the document does not teach using a copper compound as a catalyst. Besides, though the document describes using sulfolane as a solvent, it does not have a specific description such as examples.
Also, both of the above two methods have had a problem of a low yield of acrolein.